u no the sound im on about,whats the smallest portin to get the brab brab sound,
You might just get it with a small 1/2 bridge or a hooooge street port.
you would need some form of bridgeport to do it.
regards
Carl
Well i dont know what he is on about???????????? :xconfused
the noise a ported rotary makes ... sounds a little like the words in this post. Have a listen to the video of Carls car and you will know ;)
Thanks Mike, im not sure that i have ever heard it, but i bet the chicks dig it!and i want it NOW :evillaugh
:rollin + some extra words to make up 10 letters
Anyone got a link to the video?
http://www.rotorstock.com/forums/showthread.php?t=8962&referrerid=1
probably not an ideal example. it was very clear when following Dave Nixons RX3 back from the rotary parade thingy in Dave Collin\'s RX7 tho\'.
Turbo\'s kill most of the noise engines make though :(
QuoteTurbo\'s kill most of the noise engines make though
Confused. I know the people that know me will say that is a permenant problem, But HOW. At idle a bridge ported engine on a turbo car will give the same noise as a na car. the same is true for when the car is under load. Either that or i am deaf and confused :evillaugh
Quote from: aspu no the sound im on about,whats the smallest portin to get the brab brab sound,
You can get the same noise on a street port running rich at idle too.
You take out some fuel at idle and it will sound like a normal jnon brapping streetport again.
I have that twin turbo bridgeport FC video which Glenn posted a while back if anybody here can host it??
Leave the Inlets stock and remove the exhaust sleaves and open those Exahust ports then you\'ll get Overlap with stock ports. ;)
Yep, did this on my EGi :D Brap Brap Brap Braaaaaaaaaaaaap Pop Braaaaaaap Cant beat a N/A rotary with a straight through exhaust when it comes to sound affects :)
You could actually get the the brap brap noise from a standard 1973 RX-2 with the choke pulled out fully! :)
Even better - Twin Turbo bridgeport! 20MB video:
(http://www.mazdarotaryclub.com/general-videos/Twin-Turbo-Bridgeport.JPG) (http://www.mazdarotaryclub.com/general-videos/Twin-Turbo-Bridgeport.mpg)
glenn u just made my mind up 4 me, :yes
Quote from: GrizzlyLeave the Inlets stock and remove the exhaust sleaves and open those Exahust ports then you\'ll get Overlap with stock ports. ;)
i have heard you mention overlap before! have you removed the exhaust sleaves on yours?, did it make much difference?
Aaaaahhhhhh, now I know why that FD I saw a few months back sounded nothing like mine *ignorance hat removal complete* :D
Actually..the street port,even very big gives a smell degree of sound above 2000 rpm,but if you port a bridge with port overlap then you will def get that sound you are after,but if you run perif port you will get the sound.....idle speed has to be set at 2200rpm........say this to yourself and you get the sound.....bread,bread.bread...jam,jam..bread,bread,bread,jam,jam.........thats the sound.My street port runs like that..................wish i could post a audio :evillaugh
I just about remember it mate! yummmmmm.... :cool
Quote from: GrizzlyLeave the Inlets stock and remove the exhaust sleaves and open those Exahust ports then you\'ll get Overlap with stock ports. ;)
Would this cost much to do? and what parts would i be needing lol i love the sound of that rx7 on the clip :)
Any pro`s or con`s for your method lol
The cost is nil if you have the facilities at hand to remove the sleaves from the housings and do a little light machining of the ports. The bitch is you have to strip the engine to do it.
Out of interest, where can I get a housing re-chromed if I seriously screw up the porting/get flaking?
does opening the exhaust ports make any power or idle differance? dance fancy having to rev to 3000rpm to pull away lol
Removing the baffels/sleaves opens up the area behind the port by around 40-50% so it will improove flow characteristics, however without a decent manifold to take advantage of this the gains would be pretty small. My 13B n/a was running with no sleaves, mild street porting and as much porting as I was brave enough to do on new housings. (not a lot!) I then fitted a straight through exhaust system similar to the racing beat design, (two 2.5" pipes from the ports, joining into a main 3" pipe under the car, the split into two 2.5" bore tubes to the rear of the car)
Low down torque was about the same as it ever was, between 4500-7500 rpm the car was a rocket though :)
as long as the power stays rufly the same its ok because im not 2 sure what my ecu cn handle, i just want that noise lol.. so if i get the exhaust ports machined and just replace the sleeve, then i`ll have that noise?
Assuming you are running a straight through system with no turbine in the way then you should get a similar noise :)
Listen guys let me tell you something,I agree with most of what is said but....it goes a bit farther than all of that..........The exhaust ports is just one thing to bear in mind.....my limited experience is that i take out everything that is blocking the flow of exhaust air,i then open the ports even more so there is a directional flow of the gasses....this all relative to the amount of fuel put into the motor and the size and shape of the kidneys(intake ports)...i believe it is like a human being...the more you eat the more you have to c....,therefore the fuel fuel you put in the gas you generate the quicker you have to get the gas out..
All porting is directional and has to go with flow of the rotor..angles are debateable(sp),to get that sound you have to have BIG intakes (side and the kidneys) the height and the size you are prepared to go depends on the size of your ba...My street port are cut so big that i am in the water jackets already.I got no more metal to take off without doing some serious engineering.I get carried away with the milling machine :evillaugh .....Obviosly(sp) with a bridge that sound come auto and gets better as the ports are bigger,with a perihp port the sound is orgasmic.The exhaust plays a vital role.......2.5 inch headers with specified length,into 3 inch all the way through.ideally yer header size pipe is a lil bigger than yer exhaust port........etcetctetc :chat sorry guys i get carried away as i just want to share...
:yes :yes :yes :yes :yes :yes :yes :yes :yes :yes :yes
Kriss,
the only downside to a bridgeport is that you will use alot of fuel,the consumption goes through the roof.
As "OldOne" say\'s a PP will do the same.
But if you want that sound then great!bring it on!
Regards
Carl
Since when do rotorheads care about fuel consumption,AND you can port your turbo motors (small bridge) and get that brill sound...the aftermarket electronics will sort out the fuel and asumming you got a few extra injectors :3gears-lh
Carl,
why does MPG go through the roof with a bridge?, its only letting a strip of air more than a street port into the engine, if the primaries arnt done,(1/2 bridge) would it make mpg a little better than a full bridge?. how bad are we talking on a 13b tubo engine compared to a street ported engine?
bridge port = earlier opening = more overlap = more fuel blown/sucked out of the exhaust unburnt.
And for those that think turbo\'s don\'t F up engine notes ... http://media.putfile.com/LogansFDsmaller
(blatently ripped from here - http://www.rx7club.com/showthread.php?t=454580&page=2&pp=15 ) Interesting engine too ... Semi P-port :yes
the turbocharged P-Port 3 rotor drag cars don\'t sound half as good. The supercharged ones I\'ve heared sound nearly as nice though.
Hi Tony,
well the thing is that in my experience the fuel consumption goes up greatly,true,with tuning you can help it and by only doing the secondaries too,but it still is high,probably half a stock engines if you try to drive carefully depending on the port, but as "OldOne" said it does depend on how big your port is too.
If you are going to build a worthwhile port for power and not just the brap, then what happens is that your port opening duration goes up big time,think of how long that thin strip is open for,If you have more inlet timing then even on light throttle you tend to use alot more fuel as more air is entering the engine,this has to be the case also because of the very high overlap.The overlap contributes to the inlet charge being contaminated with exhaust gas.|This is mostly true with little or no boost and anything other than WOT.At WOT the whole engine becomes much more efficient and you get good scavenging from the exhaust ports,either by exhaust tuning in the case of N/A engines or the turbo helping to scavenge on boost.
There is much more to this,but if you would like to know more I can explain in more detail.
"OldOne" could you PM me? I would like to have a chat please.
Regards
Carl
Quote from: Carl"OldOne" could you PM me? I would like to have a chat please.
Regards
Carl
No he cant, he\'s not a member Carl. I think you\'ve seen Oldone\'s RX2? Tasty huh? :god
Quote from: 20B_boyNo he cant, he\'s not a member Carl. I think you\'ve seen Oldone\'s RX2? Tasty huh? :god
I think he can see my email address.
Regards
Carl
Quote from: CarlKriss,
the only downside to a bridgeport is that you will use alot of fuel,the consumption goes through the roof.
As "OldOne" say\'s a PP will do the same.
But if you want that sound then great!bring it on!
Regards
Carl
:rollin bring it on, oh i will
I was only posting from my experiences, having never done any porting work on a turbo I didnt want to say yes it will deffo make this noise and behave this way etc :D
Oldone, you got any more pics of your car, sounds like you have a Class 1 toy there, and we all like our toys on MRC :D :D :D :D :D :D
http://photobucket.com/albums/a184/eradeklerk/RX2/ some pics i took this morning
Will have to try and pop over again soon bud, for a proper demo :D
Rich
Quote from: oldonehttp://photobucket.com/albums/a184/eradeklerk/RX2/ some pics i took this morning
very nice motor.colour is cool :)
:) you know the entrance fee bud............
thanx for the compliment.....be cool to fly around the TT course or on the short circ on the isle
Quote from: oldone:) you know the entrance fee bud............
Yeah mate :D
noice ... is that an oil filter on the tailpipe :D
Quote from: MikeLMRnoice ... is that an oil filter on the tailpipe :D
yea i did,maybe to stop water n crap goin down the pipe,
So a bridge port is an like overflow pipe for your petrol tank :) the more you put in the more comes out lol :spank
Actually the video to watch is the Le Mans winning ROTOR,that sound is awsome (i know diff motor) but at idle you can have then same sound.
Tha my friends is a tukka used oil filter to stop all the **** going where it should not be going,no valves heheheheheheheh the dust goes all the way to where it should not.I only fire her up once a week so i try and keep the **** out...sorry i should not have said the s.wordhahahahhehhehehhahahahaha
good grief..read my own reply and you censor board is great,does this mean i can express myself like i want to and you will censor it ?
F****** Right..... :chat
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Nice car by the way....
I dont have to dial my handcontroller to make cool flames out the exhaust
Quote from: oldoneSince when do rotorheads care about fuel consumption,AND you can port your turbo motors (small bridge) and get that brill sound...the aftermarket electronics will sort out the fuel and asumming you got a few extra injectors :3gears-lh
Dosnt really bother me how much it uses lol i just wish petrol cost the same as it does in america lol.. we we`r there and 1 galleon was 2 dollars, i.e 1 quid!! :god
You get priorities and you get wants,having a rotor that runs and sounds good is a PRIORITY bro
I\'ve just read this Thread, I think i\'ve lost the Point somwhere? Do you just want the engine to make a Brap noise?
You are not looking for power and don\'t want to loose and MPG?
The reason it makes the Brap noise is the Overlap of the Inlet and exhaust ports. Basicly this will screw your low end performance and fuel up no end. People spend years trying to make there engines NOT! Brap so they can get good low end, So what you are asking doesn\'t make sence?
interesting thing is that a turbo bridgeport if done right will spool the turbo earlier than an extend port.
Regards
Carl
From astreet use point the brap sound sucks....cos on the freeway at 80 mph the car stutters and farts,from a race point of view i want the power band to be useable,i.e.above 5000 rpm all the time...........on the road its a pose,on the strip its a have to..........been racing the beasts since 94...low end comes from inertia (low down torque) heavy flywheel,good for street use....perms are endless...ask Carl..the customer tells you what he wants and you build t for them
Quote from: Carlinteresting thing is that a turbo bridgeport if done right will spool the turbo earlier than an extend port.
Regards
Carl
Sure does, I found the Mid range benifits of a Half bridge are worth the C**p MPG. I guess your seeing better VE.
the customer tells you what he wants and you build t for them,
well said that man,its my money n il spend it on what i like :)
interesting thing is that a turbo bridgeport if done right will spool the turbo earlier than an extend port.
Regards
Carl
ud better do it right then :cool
Quote from: GrizzlyI\'ve just read this Thread, I think i\'ve lost the Point somwhere? Do you just want the engine to make a Brap noise?
only till i no where im goin with the car ;)
Listen im so f...up that i even port
my Mc Culloch 210 strimmer...hahahaheheheheh let me at the milling machine and the dremmel tool .gagagagag
LOL ;)
Chris
no kiddin bro got the only strimmer that runs expansion pipes and on Castrol 40 mix
lol :rollin
people think im queer cos R40 to me is like a fix,i put it in the strimmer and the mower.....250ml to 20 lit of fuel..................Angela\'s Vectra dont like like it (maybe cos its DIESEL i found out)>......hahahahahahahah
Quote from: antnicuki have heard you mention overlap before! have you removed the exhaust sleaves on yours?, did it make much difference?
Yes and Yes
Its all about the Exhaust manifold to go with it. oviously with the sleaves out it will be a bigger bore size so you have to get a manifold made that matches the size. Its also important to get its lenth right.
Oviously you don\'t just open the Exhaust up and leave the Inlet so it will breath alot better but i found with mine i lost quite a bit of my low end power. I wish i had gone Secondry Bridged Inlet left the Sleaves and just matched the sleaves to the Ports. Just becouse i feel i spent alot more time messing about and got simalar if a little less Overlap with less gains in mid /high range power. I think my big Extended port would proberly last a little longer than a Bridge though?
Accepted manifold length is 48",from block to collector,from there 3" id piping to one rear muffler and 3" short tail piece.Opening of the ehaust ports is relative to your intakes....it all goes about the controlled flow of air through the rotors,how the air is directed and controlled when entering the motor...same goes about how it exits.......well built bridge will last as long as any street port.....my experience
I take it thats NA?
My Manifold is 3" Drops down to 2.5 then its 13" from the Block to the hot side of the Turbo, its also properly Divided ;)
Yeh i like Bridges but i don\'t have access to a Miller at the moment so i had to do the Job by hand. So a Bridge would have been a royal pain in the A**e my main reason i did\'nt go the Bridge Route.
Yes you will find that Era (Oldone) is talking about for naturally aspirated applications.
On the turbo bridgeports the length of exhaust runners doesn\'t really matter.Short as possible for the turbo is better.
I have found that on bridgeports that are not turboed,the length is also determined by the diameter of the headers,the smaller they are the longer they need to be until they reach the collector.
Regards
Carl
To true brother,you are spot on with the turbo lengths and spot on with the N/Applicable lengths heehege....that is why sometimes you see the dual exhaust on a near standard N/a running virtually the lenthg of the car before the collector and then to a big muffler....but you are spot on as we have checked this on the dyno many times .... :yes
Its somthing i\'ve never realy played with (NA Rotary) I just know they are loud!! LOL
If you have the experience with the n/a\'s you can make them sound as sweet as anything....but as the rpm increases you can make them sound like a superbike ! :evillaugh The cops are looking for superbike and you are trundeling along in your \'66 Beetle and they dont even look... :cool that what gives me the h..o...n when i play with all the old school stuff.......